On Mildew. 169 



It is another well known fact, that grounds in our 

 new settlements are much less exposed to mildews than 

 in our old plantations which have been often dunged. 

 The reason of this is plain upon this hypothesis, for 

 dung heaps are known in summer, to receive and retain 

 a much greater degree of heat than common earth. 



There can be no doubt therefore, but that dunged 

 lands do the same in proportion to the dung, especially 

 the new dung, laid upon them. And if so, it must oc- 

 casion a more violent ascent of the juices, and so the 

 stalk will be proportionably in more danger of bursting, 

 and of an extravasation of the juices, upon a sudden 

 chill in the stalk. 



Another fact commonly observed is, that high grounds 

 are not so exposed to mildews as lower. The reasons 

 are plain upon this hypothesis^ 1st. Because there is 

 not so much difference bet a een the weather in the day 

 and night on high grounds, as in the lower. 2d. Because 

 the greater motion of the air in the high land, may in 

 some measure prevent the stagnation of the juices. 



But most of these things are very hard to account 

 for, upon any other hypothesis I have ever seen. 



Upon this plan too, an high wind will be likely to 

 prevent a mildew ; and accordingly, I think, they are 

 never known to come in a windy night, though cold. 

 And a shower, or a rope passed over the fields, at this 

 time may do some service : as the washing and cleans- 

 ing a sore on an animal, or as any kind of motion in 

 case of stagnation of the blood and juices of our bo- 

 dies. 



But though I take this, for the reasons given, to be 

 the true cause of what are called mildews ; from the 



VOL. II. Y 



